Large modern buildings are generally constructed by building a concrete and steel frame structure, and then installing panels to define the interior and exterior walls. In many cases, the panels are made of architectural glass installed on the building by a suitable framing system. Glass panels are desirable because of the need to introduce as much natural light as possible into the building, making for a more pleasing environment and also helping to reduce energy costs. More recently, the advantages of light-diffusing translucent panels have been realized. Conventional transparent windows will transmit the sun's rays directly into the building, giving rise to excessive contrast. Light diffusing panels will diffuse the light, giving the impression of a light and airy room without excessive contrast. In a sense, such panels act as passive diffuse light sources in the building in a similar manner to fluorescent panels, but with the source of the light being natural instead of artificial.
There are two kinds of wall structure: so-called curtain walls and structural walls. Curtain walls are not self-supporting, and rely on an external rigid frame to hold the panels in place. Such walls are typically found in shop windows. In curtain walls, since the panels do not bear any load, they are relatively easy to make, and traditional double glazing is often sufficient. Structural walls, on the other hand, are self-supporting, and are typically made as an interlocking structure that can be fitted together. Such walls are not made of glass because of the excessive loads that would be imposed on the glass panels, especially when the need to provide adequate thermal insulation is taken into account. In the case of double-glazed windows, if the gap between the panes, known as lites, is too great condensation problems arise because it is very difficult to maintain a hermetic seal in the real world environment; if it is too small, the windows cannot bear the load. Such windows are typically made in a conventional manner by providing a window frame and inserting the window panels within the frame.
It is known to install insulated core, rigid skinned on the exterior of buildings as cladding, in the interior of buildings as partitions, and on the roofs of buildings both as (a) exterior cladding and (b) interior partition, and (c) interior and (d) exterior freezer panels, thus achieving a weather tight, durable, insulated, efficient, pre-finished, easily installed, appealing building envelope, freezer panel or partition.
It is also known that rigid cladding panels of metal, plastic, wood or composite materials can also be installed as stated, with or without insulation, and with or without interior rigid liner panels. These panels may be either opaque or translucent. It is also known that daylighting products can be installed into rigid exterior panel systems by installing structural framing and then installing framed window systems. It is further known that conventional framed window and louver systems can be installed into insulated core rigid skinned panel cladding systems through the use of purpose made adaptor profile frames to allow the insertion of said conventional window systems and louver systems into the panel systems. Solera™ panels by Advanced Glazings Limited provide high performance insulated translucent glazing units with the elegance, versatility and durability that come only with glass.
Examples of wall panels and glazing systems are found in the following U.S. Pat. No. 4,387,542, Integrated window and wall system; U.S. Pat. No. 5,653,073, Fenestration and insulating construction; U.S. Pat. No. 6,055,782, Extruded plastic window frame; U.S. Pat. No. 6,055,783, Unitary insulated glass unit; U.S. Pat. No. 6,286,288, Integrated multi-pane window unit; U.S. Pat. No. 6,401,428, Fenestration sealed frame insulating; U.S. Pat. No. 6,463,706, Unitary insulating glass unit; U.S. Pat. No. 6,536,182, Integrated multi-pane window unit; U.S. Pat. No. 6,662,523, Insulating glass sash assemblies; U.S. Pat. No. 6,823,643, Integrated multiple sash window unit; U.S. Pat. No. 6,868,648, Fenestration sealed frame insulating; U.S. Pat. No. 6,928,776, Window sash frame with hinged; U.S. Pat. No. 6,974,518, Method for fabricating an integrated; U.S. Pat. No. 7,100,343, Window sash glazing unit; U.S. Pat. No. 7,124,543, Window frame; U.S. Pat. No. 7,204,902, Low temperature press process; U.S. Pat. No. 6,253,511, Composite joinery; U.S. Pat. No. 6,627,128, Composite joinery; U.S. Pat. No. 6,968,659, Composite joinery.
None of these systems permits the incorporation of a glazing unit into a structural wall and which at the same time provides adequate thermal insulation.